1. Field of the Invention
The present invention generally relates to a light-emitting diode and a manufacturing method thereof, and more particularly, to a light-emitting diode with high illuminating efficiency and the manufacturing method thereof.
2. Description of the Prior Art
Until now, the light-emitting diode (LED) has already been widely-applied, such as a keyboard, a backlight module of a mobile phone monitor, an illuminative system of a vehicle, an ornamental lamp, and a remote controlling product, etc. In order to make the LED have higher functional stability and lower energy consumption, the illuminating efficiency of the LED should be required.
Please refer to FIG. 1. FIG. 1 illustrates a cross-sectional view of a well-known light-emitting diode 1. As shown in FIG. 1, the light-emitting diode 1 includes a substrate 10, a n-type GaN layer 11, an illuminating layer 12, a p-type GaN layer 13, and two electrodes 14, 15. In order to conduct the p-type GaN layer 13 and the n-type GaN layer 11 to operate the light-emitting diode 1, the electrode 15 is formed upon the p-type GaN layer 13, and the electrode 14 is formed upon the p-type GaN layer 11.
Generally, the illuminating efficiency of the light-emitting diode relates to its internal quantum efficiency and light-extraction efficiency. The internal quantum efficiency is decided by the material property and the quality; the light-extraction efficiency means the radiation proportion emitted from the inside of the light-emitting diode to the environment or the inside of the packaged epoxy resin. Although various light-emitting diodes having different structures has been disclosed, how to increase the light-extraction efficiency and illuminating efficiency of the light-emitting diode is still a question to be overcome urgently.